I’ve been wanting to do jam, preserves, and canning for a few years now, and I finally took the plunge last spring. I crawled to hell and back trying to find the best book for learning how to make jam, and when I stumbled upon The Blue Chair Jam Cookbook, the definitive guide to preserving seasonal fruit, I fell head over heels in love with their book.

I challenged myself to make jam 15 times last summer, but moving houses got in the way. I challenged myself to make jam another 15 times this spring and summer, and with only two months down (out of 6 because summer is half a year in North Carolina), I’m already almost halfway there (I just can’t stop…right after I took the photos of this batch, I started a batch of another recipe.)

I’ve run out of jars and am almost out of labels (mostly because I keep giving the jam to people.) My fridge is full of unlabeled tupperware containers with jam that wouldn’t fit into the jars, and the pyramids of quilted crystal canning jars on my pantry shelves are about to topple over. Unfortunately, I don’t have anything to put the jam on right now, so now I have to go and make english muffins or eat the jam straight out of the container (which I totally do anyway.)

The first rhubarb recipe in the book is for a rhubarb and cherry jam, which I attempted…and burned. It was one of two batches of jam that I’ve burned since I started last April. I still had leftover rhubarb, because I was hoarding it, so I tried a regular batch. Silly old me, though, I couldn’t just make a regular batch. I had to add in something odd. I had rosewater and fresh mint, so in they went! It was brilliant and inspired, and the result is refreshing, like a mojito.

Mmmmmmmojitos.

Rose is one of those flavors, like lavender and even anise, that you either enjoy or can’t stand. For a long time, I was in the “this tastes like perfume and soap” camp, but I’ve slowly moved into the “this is almost pleasant” camp. I’m still in a transitional stage, so rose madeleines will have to wait another year or two, but somehow the flavor works perfectly in this combination. Both rosewater and mint are common ingredients in Mediterranean and Middle Eastern sweets (like baklava, faloodeh, yazdi cupcakes, and halva.) The rhubarb is tart, and without the sugar it just tastes like vegetables, but with the sugar, it’s almost citrus-y. Whether you like rose or hate it, the flavor of the rosewater marries with the rhubarb so well you’ll never want to have rhubarb without it, and the subtle, refreshing mint goes well with the citrusy-ness of the rhubarb, in the same way that it pairs with the cool sweetness of watermelon.

**If you’d rather make regular rhubarb jam without the rosewater and mint, then just omit them and do everything else as written.

preparing the jars*

*I do my sterilizing and sealing in the oven, but you can use any other method (pressure, steam, boiling, etc.) For this recipe, any sealing or canning method will work.

Preheat the oven to 250 F/120 C.

Wash the jars, lids, and seals (if they have seals) with soap and warm water. Rinse everything and place all the pieces on a baking sheet.

Place the baking sheet in the oven to sanitize and dry the jars and their pieces while you make the jam. They should stay in the heated oven for at least half an hour to fully sanitize before you fill and seal them. It’ll take about half an hour or longer to finish cooking the jam from when you turn on the stove, so start cooking the jam after you’ve placed the jars in the oven.

Before you start making the jam, place a small plate and 3-5 spoons in the freezer for testing.

making the jam

You can use either fresh or frozen rhubarb for this. If using frozen, let it macerate and thaw in the pot with the sugar and lemon juice before you start cooking the jam, or else the rhubarb and/or the sugar might burn.

You can also macerate the fresh rhubarb. Maceration entails combining the produce, sugar, and lemon juice and letting it sit for a while, until the sugar has dissolved, the produce is soft, and the fruit has released liquid. The liquid produced during maceration acts as a buffer between the pan and the rhubarb so the rhubarb doesn’t burn or sear. It also helps the jam cook faster by letting the water start to evaporate sooner.

If using fresh rhubarb, you can skip the maceration, if you want.

Have the rhubarb, sugar, and lemon juice in a large, wide pot or pan. You’ll need something like a saucepan or sauté pan, or a Dutch oven, with sides deep enough to contain the jam or any foam if the mixture foams up. The pan/pot should be wide to allow for faster evaporation so your jam can thicken before it burns or overcooks. This large, copper preserving pan is the ideal tool for cooking jam, but a 3- or 4-quart saucier, saucepan, or sauté pan will also work wonderfully. The width is more important than the depth, so avoid using a stockpot or pasta pot. For 16 ounces of jam, at least 3 quarts is a good capacity for the pot.

Turn the heat on high and bring the mixture to a rapid boil, stirring occasionally to prevent burning. You’ll need to boil the mixture for about 20 minutes or so, until the rhubarb breaks down, the mixture thickens, and the foam subsides. The jam will eventually turn darker and gloppy like pudding. As it cooks more, you’ll notice the bubbles become larger and scarcer, and a thick, lightly-colored foam will form in the middle of the jam. Stir the mixture occasionally but keep the heat up. If you notice the jam sticks to the bottom of your pan or if you notice any burning, turn the heat down.

After about 25 – 30 minutes total, once the mixture is thick like mud or pudding and the bubbles become larger and rarer, whisk in the rosewater and whole sprigs of mint.

Turn off the stove and let the jam rest for about 5 minutes to steep/infuse the mint. Leave the whole mint the jam while you’re testing, removing it you’re ready to fill the jars.

testing the jam

Using a large spoon or ladle, skim off any thick, pale foam from the surface and discard.

Take one of the frozen spoons out of the freezer, and using another spoon, transfer about half a spoonful of jam from the unfrozen spoon to the other. Replace the chilled spoon in the freezer and let it rest for 3-5 minutes. Your goal is to rapidly chill the jam so you can see whether it’s thick enough at room temperature (it will always be thicker when it’s cold and thinner when it’s warm/hot.) Freezing the jam brings it down to room temperature fast enough for you to test it multiple times and finish cooking the jam without having to wait too long. When you’re ready to test the jam, the underside of the spoon should be room temperature, neither warm nor cold. Rhubarb jam, unlike most fruit jams, doesn’t thicken completely, so it will run a little bit. When you tilt the spoon vertically, you may see the jam run just a little bit, like thick syrup.

If it seems too thin to you, turn the stove back on and continue cooking the jam**. Taste the jam every time you test it, to determine if you need more of the rose or mint. As soon as the mint is strong enough, you can discard the herb. If you need more rosewater, add more before filling the jars, and if you need more mint flavor, leave the herbs in until the flavor is strong enough.

**Your whole sprigs of mint are still in the jam, and normally, cooking fresh herbs is taboo, but if you need more of the mint flavor, leave them in until they have infused enough for you, even through the continued cooking.

Keep in mind, though, that strong flavors will become more mild once the jam cools.

The rest of the frozen spoons are for you to continue testing.

Bring your jam back to a boil and let it cook for about five minutes, stirring frequently to prevent sticking and burning. If you see it starting to the stick to the bottom of the pan, reduce the heat a bit. Test the jam again after 5 – 10 minutes of cooking, following the same process. Keep testing and cooking until it’s your desired consistency.

Once the jam is as thick as you want it after the freezer test, move on to filling and sealing the jars.

sealing the jars

You only need to seal the jars if you plan on keeping the jam for a long time at room temperature. If you’re going to eat the jam within 2 weeks, or keep it in the freezer, you don’t need to go through the sealing process after you fill the jars. You can even use regular glass jars or plastic containers if you plan to freeze or refrigerate the jam.

Refrigerated jam (unsealed) lasts about 2 weeks. Frozen jam will last about 6 months, and properly-sealed jam can last up to a year at room temperature.

As with sanitizing the jars, you can follow any sealing process you want (the manufacturer will have added directions to the packages of your jars.)

Remove the baking sheet of jars and jar pieces from the oven and transfer everything to a cooling rack while you fill each jar (this is just because it’s easier to fill, seal, and transfer the jars from the cooling rack back onto the baking sheet, and so you avoid spilling jam on the hot baking sheet.)

Use a ladle or spoon (a flexible silicone ladle is the best tool for this, I’ve found) to fill each jar to within 1/4″ (~0.75 cm) of the rim and use a damp paper towel to wipe the rim of the jar clean. There shouldn’t be any jam stuck to the top or outside of the jar before you put the seal on.

Place the seal on your jar and screw the lid band on snugly (not as tightly as possible, but almost all the way.) Once all of your jars are filled, place them all back onto the baking sheet (if it’s not clean, get another one), and place the baking sheet in the oven. The filled and sealed jars need to sit in the hot oven (250 F/120 C) for at least 15 minutes to re-sanitize and create a vacuum so they seal themselves.

Any jam that you couldn’t fit into the jars can be stored in an airtight container in the refrigerator or freezer.

After the filled and sealed jars have been in the oven for 15 – 20 minutes, take them out and transfer them all to a cooling rack. Don’t disturb the jars until they’re all fully sealed and cooled. You’ll hear popping noises (once per jar) as the lids seal themselves. They should all be sealed within about 10 minutes from taking them out of the oven. You can test the seals by pressing down in the middle with a finger: if you feel a popping, the lid isn’t sealed. If, after at least 10 minutes and once the jars are cooled, any of the seals are still open, you can put them back in the hot oven again for 15 – 20 minutes, or you can freeze or refrigerate them.

Once you release the seal from a sealed jar, store the jam in the refrigerator or freezer.